Part II: Metaphors, and why this one is interesting
In the last post, I used an example from Jeanne Fahnestock’s Rhetorical Figures in Science to show what productive figuration looks like. Specifically, I discussed the figure incrementum and how it has provided a conceptual framework for research in evolutionary theory and astronomy.
When working with a metaphor, we want the same generative potential. We should expect the metaphor to provide a conceptual framework that allows researchers to look at something in a new way, to ask new questions, or to make new predictions. In every conceptual metaphor, there is a target domain and a source domain. The target is the object to which attributes are ascribed; the source is the object from which attributes are borrowed. In the language/genes metaphor, genes are the source, and linguistic structures are the target.
We shouldn’t expect every attribute of the source to mirror every attribute of the target at every step and in every way imaginable—we’re not talking about 1:1 correspondence here. Rather, a productive metaphor should allow us to see some attribute of the target in some way that was hitherto hidden before the comparison to the source was made. A metaphor, guided by the attributes of the source domain, selects and highlights certain features of the target domain (while, of course, deflecting other, perhaps more defining features—no metaphor is free. We’ll return to this epistemological danger later on.)
So. Genes and linguistic structures. I’m interested in this comparison because I’m interested in the origins and evolution of language. One of the great questions in science is whether language evolved from gesture and vocalization—becoming gradually more complex through increased socialization, mental awareness, and IQ—or whether language arose relatively quickly in a specific population, the result of a mutation or, more likely, a host of mutations.
I have to admit that a good prima facie case can be made for the latter view; this is the view held by Chomsky and most American linguists. Language, after all, operates on the basis of complex structures and lightning-fast computations, traits which make comparisons to animal vocalizations seem quaint (birds and chimps don’t inflect for case or subordinate clauses). We don’t see a ‘continuum of language’ in nature. Human language is only human language once it’s human language, regardless of what you’ve heard about bird and whale songs from the kumbaya types who chant parochial clichés about “similarities between humans and animals that make people feel uneasy.”
However, even if we admit that language is a peculiarly human ability, there’s no necessary reason to assume that it is based on polygenic mutations alone. Social pressures on linguistic change are well documented; so, too, is the fact that not all languages exhibit the same degree of complexity, which is what we should expect if language is not the result of a human-specific cognitive adaptation. There’s evidence that points away from the Chomsky view, in other words.
If the evolution of linguistic structures is analogous to genetic replication, it would be very suggestive in relation to the debate over language origins. Suggestive, not definitive—linguistic structures and genes might be analogous, not homologous, and so the metaphor wouldn’t necessarily prove anything one way or the other. It would simply be interesting—and would suggest that language is perhaps grounded in biology rather than socialization—if languages replicate themselves along genetic lines.